中国保安族线粒体DNA D-环区遗传多态性的研究

目的：以遗传群体为对象，观察线粒体DNA的群体遗传特点，为研究西北少数民族的起源提供科学依据，并为法医学鉴定提供线粒体DNA序列多态性的基础数据。方法：应用PCR扩增产物直接测序法，对98例保安族无关个体线粒体DNA D-环区HVSⅠ进行测序分析。结果：在mtDNA高变区Ⅰ(HVSⅠ)16091～16418之间与Anderson序列比较共发现有66处碱基突变，62个单倍型，碱基突变的主要形式为碱基替代，其中转换87％，颠换11％，碱基插入1％，碱基缺失0．5％．保安族线粒体DNA HVS Ⅰ区基因差异度为0．9862，偶合概率为0.0237。结论：保安族与其他群体比较有其独特的线粒体DNA序列遗传特点，与亚洲其他人种及高加索人种有明显差异。保安族线粒体DNA序列多态性不仅有别于西方人种，也与其他东亚人种不同，线粒体DNA控制区HVS Ⅰ序列多态性可用于法医学个体识别及亲权鉴定。

Polymorphism of mitochondrial DNA D-loop region in Chinese BAOAN ethnic group

AIM: To investigate the mitochondrial DNA sequence polymorphism in Chinese BAOAN ethnic group and to provide basic data for ethnic origin investigation and forensic purpose. METHODS: Genomic DNA was extracted from the whole blood of 98 unrelated individuals of Chinese BAOAN ethnic group by standard chelex 100 method. The sequence polymorphism was determined by PCR amplification and direct sequencing. RESULTS: Sixty six polymorphic sites and 62 haplotypes were identified in mtDNA D loop region (np16091 16418) . The genetic diversity was calculated to be 0.9862, and the genetic identity was 0.0237. CONCLUSION: There are some particular polymorphism sites in Chinese BAOAN ethnic group, and these sites provide an important basis to investigation of the origin of BAOAN and the relationship between BAOAN and other ethnic groups. The result also suggests that sequence polymorphism (np16091 16418) in human mitochondrial DNA can be an useful tool for forensic identity.